Low temperature stable aqueous formulations of N-(n-butyl) thiophosphoric triamide

Abstract

The present disclosure relates to a low temperature stable aqueous formulation of N-(n-butyl) thiophosphoric triamide (NBPT) with stability against crystallization and/or freezing upon exposure to low temperatures of 0° C. or below. Formulations of the present disclosure may also contain water-soluble agents such as microbial strains. The present disclosure also provides methods to make and use the formulation according to the present disclosure.

We claim: 
     
         1 . A formulation comprising:
 i) N-(n-butyl) thiophosphoric triamide (NBPT) in an amount ranging from about 25% to about 40% by weight;   ii) water in an amount ranging from about 7% to about 25% by weight; and wherein the water optionally comprises a water-soluble agent; and   iii) a polar aprotic solvent in an amount ranging from about 30% to about 50% by weight; and   iv) a glycol and/or a glycol derivative in an amount ranging from about 1% to about 25% by weight; and/or   v) an alkylene glycol alkyl ether in an amount ranging from about 0.1% to about 25% by weight;   wherein each component is present in amount by weight of the total formulation;   wherein the formulation is stable for at least 2 weeks at 0° C.   
     
     
         2 . The formulation of  claim 1 , wherein the water comprises a water-soluble agent. 
     
     
         3 . The formulation of  claim 2 , wherein the water-soluble agent is a biological agent. 
     
     
         4 . The formulation of  claim 3 , wherein the biological agent is an agriculturally beneficial  Bacillus  species selected from the group of strains consisting of  Bacillus amyloliquefaciens  (ATCC 23842),  Bacillus licheniformis  (ATCC 14580),  Bacillus licheniformis  (B-642),  Bacillus licheniformis  (B-14368),  Bacillus thuringiensis  (ATCC 10792),  Bacillus thuringiensis  (HD-17),  Bacillus thuringiensis  (HD-1),  Bacillus pumilus  (NRS-272), and any combination thereof. 
     
     
         5 . The formulation of  claim 1 , further comprising a dye. 
     
     
         6 . The formulation of  claim 1 , wherein the polar aprotic solvent is selected from the group consisting of N-methyl-2-pyrrolidinone, dimethyl sulfoxide, dimethylformamide, and combinations thereof. 
     
     
         7 . The formulation of  claim 1 , wherein the alkylene glycol alkyl ether is selected from the group consisting of diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monopentyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, triethylene glycol monopentyl ether, triethylene glycol monoisopropyl ether, triethylene glycol monoisobutyl ether, triethylene glycol monohexyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol monopropyl ether, tetraethylene glycol monobutyl ether, tetraethylene glycol monopentyl ether, tetraethylene glycol monoisopropyl ether, tetraethylene glycol monoisobutyl ether, tetraethylene glycol monohexyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopentyl ether, dipropylene glycol monoisopropyl ether, dipropylene glycol monoisobutyl ether, dipropylene glycol monohexyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tripropylene glycol monopentyl ether, tripropylene glycol monoisopropyl ether, tripropylene glycol monoisobutyl ether, tripropylene glycol monohexyl ether, and combinations thereof. 
     
     
         8 . The formulation of  claim 1 , wherein the weight ratio of NBPT to water is from about 1.8:1 to about 6.0:1. 
     
     
         9 . The formulation of  claim 1 , wherein the weight ratio of polar aprotic solvent to glycol and/or glycol derivative to alkylene glycol alkyl ether to water is from about 60:30:1:10 to about 70:40:1:18. 
     
     
         10 . The formulation of  claim 1 , wherein NBPT is present in an amount of about 26.22% by weight; a polar aprotic solvent is present in an amount of about 47.11% by weight; a glycol and/or a glycol derivative is present in an amount of about 1.5% by weight; an alkylene glycol alkyl ether is present in an amount of about 0.86% by weight; water is present in an amount of about 14.28% by weight; and a dye is present in an amount of about 0.57% by weight. 
     
     
         11 . The formulation of  claim 1 , wherein the polar aprotic solvent is dimethyl sulfoxide. 
     
     
         12 . A process of preparing a formulation of  claim 1  comprising:
 mixing a concentrate comprising the N-(n-butyl) thiophosphoric triamide (NBPT); 
 the glycol and/or the glycol derivative; the alkylene glycol alkyl ether; the polar aprotic solvent; and optionally a dye with the water, wherein the water optionally comprises a water-soluble agent. 
 
     
     
         13 . A method for promoting plant growth, plant productivity, and/or soil quality comprising applying an effective amount of the formulation of  claim 1  to a plant, plant part, plant seed, and/or soil. 
     
     
         14 . An NBPT concentrate comprising:
 i) N-(n-butyl) thiophosphoric triamide (NBPT) in an amount ranging from about 37% to about 60% by weight;   ii) a glycol and/or a glycol derivative in an amount ranging from about 0.2% to about 2% by weight;   iii) an alkylene glycol alkyl ether in an amount ranging from about 0.5% to about 20% by weight; and   iv) a polar aprotic solvent in an amount ranging from about 40% to about 70% by weight;   wherein each component is present in amount by weight of the total formulation.   
     
     
         15 . The concentrate of  claim 14 , wherein the glycol is dipropylene glycol. 
     
     
         16 . The concentrate of  claim 14 , wherein the alkylene glycol alkyl ether is monomethyl ether or triethylene glycol monopropyl ether. 
     
     
         17 . The concentrate of  claim 14 , wherein the polar aprotic solvent is selected from the group consisting of N-methyl-2-pyrrolidinone, dimethyl sulfoxide, dimethylformamide, and combinations thereof. 
     
     
         18 . The concentrate of  claim 14 , wherein NBPT is present in an amount of about 41.06% by weight; a glycol and/or a glycol derivative is present in an amount of about 1.2% by weight; an alkylene glycol alkyl ether is present in an amount of about 5.47% by weight; and a polar aprotic solvent is present in an amount of about 52.27% by weight. 
     
     
         19 . A kit comprising:
 (i) Part A, wherein Part A comprises a solution comprising N-(n-butyl) thiophosphoric triamide (NBPT) in an amount ranging from about 37.0% to about 60.0% by weight; a polar aprotic solvent in an amount ranging from about 40.0% to about 70.0% by weight; a glycol and/or a glycol derivative in an amount ranging from about 0.2% to about 2% by weight; and an alkylene glycol alkyl ether in an amount ranging from about 0.5% to about 20.0% by weight; wherein each component is present in an amount by weight of the total solution; and   (ii) Part B, wherein Part B comprises an aqueous suspension comprising one or more  Bacillus  species selected from the group consisting of  Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus thuringiensis , and  Bacillus pumilus,      wherein each of Part A and Part B is contained in a separate container.